Plants having increased and/or improved biomass are useful for agriculture, horticulture, biomass to energy conversion, paper production, plant product production, and other industries. In particular, there is a need for increases in biomass for dedicated energy crops such as Panicum virgatum L. (switchgrass), Miscanthus x gigantus (miscanthus), Sorghum sp., and Saccharum sp. (sugar cane). Throughout human history, access to plant biomass for both food and fuel has been essential to maintaining and increasing population levels. Scientists are continually striving to improve biomass in agricultural crops. The large amount of research related to increasing plant biomass, particularly for dedicated energy crops, indicates the level of importance placed on providing sustainable sources of energy for the population. The urgency of developing sustainable and stable sources of plant biomass for energy is underscored by current events, such as rising oil prices. The amount of biomass produced by plants is a quantitative trait affected by a number of biochemical pathways.